The study involves 4 protocols. The first protocol (I) concerns surveillance of the population of patients with bladder tumor entering the collaborating institutions. 645 patients entered between January 1, 1974 and June 1, 1975. Relevant clinical, occupational, radiologic and pathologic data is being obtained from these patients and it is hoped that it will be useful in defining prognostic factors. Protocol II--a protocol to investigate non-cancerous urothelium by selected mucosal biopsies and cytology in an attempt to determine its neoplastic potential, has demonstrated that a considerable number of these biopsies that were thought to be non-cancerous by cystoscopic observation have on histological evaluation either atypia or malignancy (ca-in-situ) present. Protocol III--A protocol to determine the effectiveness of intravesical instillation of thiotepa on non-invasive bladder carcinoma and the recurrence rate of tumor in these patients. Protocol IV--A protocol to determine the results of external irradiation and combined irradiation and surgery as definitive therapy for patients with invasive primary bladder cancer. Patients have been entered since August 1974. It is hoped that these latter 2 protocols will define precisely the effectiveness of existing treatments and provide a base of comparison for the initial evaluation of newer methods of therapy.